开发有效的风机电磁暂态模型是进行海上风电并网研究的基础。根据不同生产厂家所提供的直驱风机模型,提出了一种基于厂家黑盒模型的直驱风机电磁暂态建模方法。利用厂家所提供的模型测试数据解析风机的故障响应特性,推导了不同厂家在电...开发有效的风机电磁暂态模型是进行海上风电并网研究的基础。根据不同生产厂家所提供的直驱风机模型,提出了一种基于厂家黑盒模型的直驱风机电磁暂态建模方法。利用厂家所提供的模型测试数据解析风机的故障响应特性,推导了不同厂家在电压故障下有功和无功功率响应表达式,包括故障期间的穿越控制过程及不同过程间的暂态切换策略。提出了加权平均压降的风电场等值方法,采用自主研发的全电磁暂态仿真软件(power system model,PSModel)对我国广东某海上风电场进行全电磁暂态建模。根据稳态潮流及暂态特性结果验证了模型可通过系统测试,且有效实现了海上风电场的全电磁暂态建模,从而为该风场接入大电网后的安全稳定分析提供了研究基础。展开更多
Simulink is a visual simulation tool in MATLAB;?through Simulink software,?to establish a model can reduce the amount of programming workload,?and?improve the efficiency of the establishment of automotive models.?The ...Simulink is a visual simulation tool in MATLAB;?through Simulink software,?to establish a model can reduce the amount of programming workload,?and?improve the efficiency of the establishment of automotive models.?The ride comfort of the vehicle is a measure of the most basic indicators of a car performance.?By establishing a ride comfort model in Matlab/Simulink, the wheel motor electric vehicle mainly affects the smoothness of the car mainly in the following aspects:?pavement, tire, suspension, motor and so on.?Through the establishment of the above model,?we?can effectively study the wheel motor drive electric vehicle ride comfort research.展开更多
The ride comfort experimental assessment of crawler off-road vehicle is relatively overlooked, and is expensive and difficult to execute with higher and higher ride comfort performance requirements. To trade off betwe...The ride comfort experimental assessment of crawler off-road vehicle is relatively overlooked, and is expensive and difficult to execute with higher and higher ride comfort performance requirements. To trade off between precise and cost, an experimental method based on the similitude theory is proposed. Under the guidance of the similitude theory, a 1:5 crawler power chassis scale model equipped with a kind of variable stiffness suspension system is used. The power spectrum density(PSD), the root mean square(RMS) of weighed acceleration, peak factor, average absorbed power(AAP) and vibration dose value(VDV) are selected as ride comfort evaluation indexes, and tests results are transformed via similarity indexes to predict the performance of full-scale power chassis. PSD shows that the low-order natural frequency of the vertical natural frequency(z axis) is 1.1 Hz, and the RMS, AAP and VDV values indicate the ride comfort performance of this kind of power chassis is between the "A little uncomfortable" and "Rather uncomfortable". From the results, low-order vertical natural frequency, obtained by PSD, validates that the similarity relationship between two models is satisfied, and 1:5 scale model used in experiment meets the similarity relationship with the full-scale model; consequently, the ride comfort prophase evaluation with the 1:5 scale model is feasible. The attempt of applying the similitude theory to crawler vehicle ride comfort test study decreases the cost and improves the test feasibility with sufficient test precise.展开更多
分布式新能源出力具有波动性,且接入位置不均匀,当其规模化接入配电网后将增大发生故障的概率。在配电网发生故障时,增强并网电力电子设备的低电压穿越(low voltage ride through,LVRT)性能是保障配电网稳定运行的技术关键,已成为当前...分布式新能源出力具有波动性,且接入位置不均匀,当其规模化接入配电网后将增大发生故障的概率。在配电网发生故障时,增强并网电力电子设备的低电压穿越(low voltage ride through,LVRT)性能是保障配电网稳定运行的技术关键,已成为当前研究热点之一。以柔性互联配电网中的柔性电力电子开关(soft open point,SOP)为对象,结合配电网馈线线路阻抗特性,提出一种基于线路阻抗特性的SOP LVRT控制策略。首先,分析线路阻抗对换流器接入公共耦合点(point of common coupling,PCC)电压的影响,并推导出利用换流器注入功率抬升电压的机理;其次,提出基于馈线出线侧及换流器本地量测数据的PCC点至故障点的线路等效阻抗测量方法;然后,构建基于阻抗测量法的SOP LVRT整体策略;最后,在PSCAD仿真平台上验证所提控制策略,结果表明,在不同电压跌落范围内,所提SOP LVRT控制策略能同时补偿有功功率和无功功率,较仅采用无功补偿能更明显提升PCC电压水平。展开更多
文摘开发有效的风机电磁暂态模型是进行海上风电并网研究的基础。根据不同生产厂家所提供的直驱风机模型,提出了一种基于厂家黑盒模型的直驱风机电磁暂态建模方法。利用厂家所提供的模型测试数据解析风机的故障响应特性,推导了不同厂家在电压故障下有功和无功功率响应表达式,包括故障期间的穿越控制过程及不同过程间的暂态切换策略。提出了加权平均压降的风电场等值方法,采用自主研发的全电磁暂态仿真软件(power system model,PSModel)对我国广东某海上风电场进行全电磁暂态建模。根据稳态潮流及暂态特性结果验证了模型可通过系统测试,且有效实现了海上风电场的全电磁暂态建模,从而为该风场接入大电网后的安全稳定分析提供了研究基础。
文摘Simulink is a visual simulation tool in MATLAB;?through Simulink software,?to establish a model can reduce the amount of programming workload,?and?improve the efficiency of the establishment of automotive models.?The ride comfort of the vehicle is a measure of the most basic indicators of a car performance.?By establishing a ride comfort model in Matlab/Simulink, the wheel motor electric vehicle mainly affects the smoothness of the car mainly in the following aspects:?pavement, tire, suspension, motor and so on.?Through the establishment of the above model,?we?can effectively study the wheel motor drive electric vehicle ride comfort research.
基金Supported by Special Fund for Argo-scientific Research in the Public Interest,China(Grant No.201203024)National Natural Science Foundation of China(Grant No.51175498)
文摘The ride comfort experimental assessment of crawler off-road vehicle is relatively overlooked, and is expensive and difficult to execute with higher and higher ride comfort performance requirements. To trade off between precise and cost, an experimental method based on the similitude theory is proposed. Under the guidance of the similitude theory, a 1:5 crawler power chassis scale model equipped with a kind of variable stiffness suspension system is used. The power spectrum density(PSD), the root mean square(RMS) of weighed acceleration, peak factor, average absorbed power(AAP) and vibration dose value(VDV) are selected as ride comfort evaluation indexes, and tests results are transformed via similarity indexes to predict the performance of full-scale power chassis. PSD shows that the low-order natural frequency of the vertical natural frequency(z axis) is 1.1 Hz, and the RMS, AAP and VDV values indicate the ride comfort performance of this kind of power chassis is between the "A little uncomfortable" and "Rather uncomfortable". From the results, low-order vertical natural frequency, obtained by PSD, validates that the similarity relationship between two models is satisfied, and 1:5 scale model used in experiment meets the similarity relationship with the full-scale model; consequently, the ride comfort prophase evaluation with the 1:5 scale model is feasible. The attempt of applying the similitude theory to crawler vehicle ride comfort test study decreases the cost and improves the test feasibility with sufficient test precise.
文摘分布式新能源出力具有波动性,且接入位置不均匀,当其规模化接入配电网后将增大发生故障的概率。在配电网发生故障时,增强并网电力电子设备的低电压穿越(low voltage ride through,LVRT)性能是保障配电网稳定运行的技术关键,已成为当前研究热点之一。以柔性互联配电网中的柔性电力电子开关(soft open point,SOP)为对象,结合配电网馈线线路阻抗特性,提出一种基于线路阻抗特性的SOP LVRT控制策略。首先,分析线路阻抗对换流器接入公共耦合点(point of common coupling,PCC)电压的影响,并推导出利用换流器注入功率抬升电压的机理;其次,提出基于馈线出线侧及换流器本地量测数据的PCC点至故障点的线路等效阻抗测量方法;然后,构建基于阻抗测量法的SOP LVRT整体策略;最后,在PSCAD仿真平台上验证所提控制策略,结果表明,在不同电压跌落范围内,所提SOP LVRT控制策略能同时补偿有功功率和无功功率,较仅采用无功补偿能更明显提升PCC电压水平。